quantization.cpp

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#include "quantization.h"

#include "hls.h"
#include "tables.h"

namespace pcc {

//============================================================================

Quantizers
deriveQuantSteps(
  const AttributeParameterSet& attr_aps, const AttributeBrickHeader& abh)
{
  int sliceQpLuma = attr_aps.init_qp;
  int sliceQpChroma = attr_aps.init_qp + attr_aps.aps_chroma_qp_offset;

  if (attr_aps.aps_slice_qp_deltas_present_flag) {
    sliceQpLuma += abh.attr_qp_delta_luma;
    sliceQpChroma += abh.attr_qp_delta_chroma;
  }

  int qpShiftLuma = sliceQpLuma / 6;
  int qpShiftChroma = sliceQpChroma / 6;

  return {kQpStep[sliceQpLuma % 6] << qpShiftLuma,
          kQpStep[sliceQpChroma % 6] << qpShiftChroma};
}

//============================================================================

}  // namespace pcc